System Design and Method for Verifying 3D Dosimetric Imaging (SJ-15-0022)

St. Jude Reference #SJ-15-0022

Description

This invention is an ionizing radiation-induced acoustic computed tomography (RACT) scanner used to guide delivery and verification of the accuracy of delivery of a therapeutic ion beam.

Charged particle therapy treatments, especially proton therapy, are increasing; however, present day proton beam therapies lack adequate verification of the dose delivered to a patient, and its exact distribution in the human body. While the initial parameters of the beam can be controlled, the exact delivery of the beam remains uncertain due to many factors (tumor shrinking, orphan motion, uncertainty in the patient setup, the specificity of the treatment planning algorithm, and in homogeneities in the human body). The ability to verify the position of the distal edge and lateral displacement of the beam is significant to treatment accuracy and patient wellbeing.

Current treatment quality assurance methods to monitor these parameters include positron emission tomography (PET) and the detection of prompt gammas (PGs). Weaknesses in these methods include sensitivity, modest spatial resolution, post-treatment assessment (for PET method), and non-linearity and accuracy of the method relative to dose deposited. Thus, the need for a better diagnostic method of delivery and verification of accuracy.